758: Predictors of preterm birth after emergent cerclage in a twin gestation

Abstract

To identify patient characteristics associated with preterm birth (PTB) prior to 28 weeks after emergent cerclage and to identify any differences specific to twin gestations. This is a retrospective cohort of women who underwent an exam-indicated cerclage at a single university hospital between January 1, 1980 and December 31, 2013. Patient characteristics associated with PTB < 28 weeks were identified in bivariable analysis. A multivariable logistic regression was then performed to identify if any of these clinical associations were modified in a twin gestation. During the study period, 442 women underwent an exam-indicated cerclage: 104 twins and 338 singletons. Of these, 121 (35.8%) of the singletons and 35 (33.7%) of the twins delivered prior to 28 weeks. In bivariable analysis, neither maternal age nor race were associated with PTB < 28 weeks. Earlier gestational age at cerclage placement was associated with a decreased odds of PTB < 28 weeks, whereas more advanced cervical dilation, a shorter cervical length, and the presence of membrane prolapse were associated with an increased odds of PTB < 28 weeks. Interaction terms were created between twin gestation and each of the patient characteristics associated with PTB < 28 weeks. A logistic regression was performed including all patient factors significantly associated with PTB < 28 weeks, gestational pleurality, and any significant interaction terms. Results are shown in Table 1. Early gestational age at cerclage placement, cervical dilation, and prolapsing membranes are all significantly associated with PTB <28 weeks in women undergoing emergent cerclage placement independent of gestational pleurality. A short cervical length (< 2cm) at the time of cerclage placement is a risk factor for PTB < 28 weeks in twin but not singleton gestations.Tabled 1 Open table in a new tab